212 THE CASE AGAINST EVOLUTION 



modification of personality itself, but to a modification in the 

 perception of personality. Since this perception is, as we 

 shall see, extrinsically dependent on cerebral imagery, any 

 neuropathic affection is liable to modify the perception of per- 

 sonality by seriously disturbing the imagery, on which it 

 depends. But {pace Wundt and James) the perception of 

 personality is one thing, and personality itself quite another. 

 Perception does not produce its objects, but presupposes them, 

 and self-perception is no exception to this rule. Introspec- 

 tion, therefore, does not create our personality, but reveals and 

 represents it. If then to the intuition of consciousness our per- 

 sonality appears as an unchanging principle that remains 

 always substantially identical with itself, it follows that this 

 perception must be terminated by something more durable 

 than a flux of transient molecules or a stream of fleeting 

 thought. Unless this perceptive act has for its object some 

 unitary and uniformly persistent reality distinct from our com- 

 posite, corruptible bodies, and not identified with our tran- 

 sitory thoughts, this sense of permanent personal identity 

 would be utterly impossible. Materialism, which recognizes 

 nothing more in man than a decaying organism, a mere vortex 

 of fluent molecules, is at a loss to account for our conscious- 

 ness of being always the same person. Phenomenalism, which 

 identifies mind or self with the "thought-stream," is equally 

 impotent to account for this sense of our abiding sameness. 



James' attempt at a phenomenalistic explanation of the 

 persistent continuity of self, on the assumption that each 

 passing thought knows its receding predecessor and be- 

 comes known, in turn, by its successor, is puerile. 

 To pass over other flaws, this absurd theory encounters an 

 insuperable difficulty in sleep, which interrupts, for a con- 

 siderable interval, the flow of conscious thought. Thought 

 is a transient reality, which passes, so far as its actuality is 

 concerned, and can only remain in the form of a permanent 

 effect. Unless, therefore, there were some persistent medium 

 in which the last waking thought could leave a permanent 



